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1.
Microb Pathog ; 188: 106550, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38262494

RESUMO

Cytokines of the interleukin (IL)-1 superfamily including the different IL-36 isoforms, have been reported as mediators of acute and chronic inflammation in human skin diseases, such as psoriasis. Here, we demonstrated for the first time that Sporothrix schenckii and S. brasiliensis, the fungi that cause subcutaneous infection sporotrichosis, can induce the expression of IL-36α, IL-36γ and IL-36Ra in human keratinocytes and primary peripheral blood mononuclear cells (PBMCs). Specifically, IL-36γ was differentially expressed by keratinocytes stimulated with Sporothrix yeasts when compared to the commensal microorganism Staphylococcus epidermidis. The exposure of keratinocytes to 24 h or 7-days culture supernatant of PBMCs stimulated with Sporothrix induced higher IL-36γ production compared to direct stimulation of keratinocytes with the live fungus. We identified that IL-36γ mRNA expression in keratinocytes is increased in the presence of IL-17, TNF, IL-1ß and IL-1α and these cytokines may act synergistically to maintain IL-36γ production. Lastly, using a cohort of 164 healthy individuals, we showed that individuals carrying variants of the IL36G gene (rs11690399 and rs11683399) exhibit increased IL-36γ production as well as increased innate cytokine production after Sporothrix exposure. Importantly, stimulation of PBMCs with recombinant IL-36γ increased the production of IL-1ß and IL-6, while IL-36Ra were able to decrease the concentration of these cytokines. Our findings contribute to the understanding of the pathogenesis of sporotrichosis and suggest that IL-36γ may be involved in maintaining the cytokine loop that leads to tissue destruction by exacerbating the immune response in sporotrichosis. Of high interest, we present the IL-36 signalling pathway as a potential new therapeutic target.


Assuntos
Sporothrix , Esporotricose , Humanos , Citocinas/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Queratinócitos , Leucócitos Mononucleares , Sporothrix/genética
2.
Cell Immunol ; 378: 104555, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35696852

RESUMO

Sporotrichosis is a deep mycosis caused by dimorphic species of the genus Sporothrix, with differences in pathogenicity between S. schenckii and S. brasiliensis species. Recently, it was discovered that the cell wall peptidorhamnomannan (PRM) from S. brasiliensis has additional unknown rhamnose residues. We hypothesize that the structural differences of Sporothrix spp PRMs impact the host's immune response and may explain the severity of sporotrichosis caused by S. brasiliensis. We demonstrate that S. brasiliensis yeasts and its PRM (S.b PRM) induced a strong inflammatory response in human PBMCs, with high production of TNF-α, IL-6 and IL-1ß and induction of T-helper cytokines IFN-γ, IL-17 and IL-22. In contrast, S. schenckii yeasts and its PRM induced higher concentrations of interleukin-1 receptor antagonist (IL-1Ra), which resulted in low production of T-helper cytokines such as IL-17 and IL-22. CR3 and dectin-1 were required for cytokine induction by both PRMs, while TLR2 and TLR4 were required for the response of S.s PRM and S.b PRM, respectively. IL-1ß and IL-1α production induced by S. brasiliensis yeasts and S.b PRM were dependent on inflammasome and caspase-1 activation. S. schenckii and S.s PRM were able to induce IL-1ß independent of ROS. In conclusion, these findings improve our understanding of the pathogenesis of Sporothrix spp. by reporting differences of immunological responses induced by S. schenckii and S. brasiliensis. The study also opens the gateway for novel treatment strategies targeting local inflammation and tissue destruction induced by S. brasiliensis infection through IL-1 inhibition.


Assuntos
Sporothrix , Esporotricose , Citocinas , Glicoproteínas , Humanos , Interleucina-17 , Esporotricose/patologia
3.
Fungal Genet Biol ; 140: 103397, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32325170

RESUMO

Microbial interactions may impact patient's diagnosis, prognosis and treatment. Sporotrichosis is a hyperendemic neglected zoonosis in Brazil, caused by Sporothrix brasiliensis. Four pairs of clinical isolates of Sporothrix were recovered from four diseased cats (CIM01-CIM04, two isolates per animal) raising the possibility of coinfection in a sporotrichosis hyperendemic area, Brazil. Each isolate of the pair had distinct pigmentation in mycological culture, and was designated as "Light" or "Dark", for low and high pigmentation, respectively. Dark isolates reacted strongly with monoclonal antibodies to melanin (p ≤ 0.05) by both ELISA and FACS quantitation, and displayed a ring pattern with some regions exhibiting higher punctuated labeling at cell wall by immunofluorescence. In turn, Light isolates reacted less intensely, with few and discrete punctuated labeling at the cell wall. PCR identified all isolates as S. brasiliensis, MAT1-2 idiomorph. Sequencing of ß-tubulin and calmodulin genes followed by phylogenetic analysis placed all eight isolates within the same cluster as others from the Brazilian hyperendemic area. The ability of these strains to stimulate cytokine production by human PBMCs (Peripheral blood mononuclear cells) was also analyzed. CIM01 and CIM03 Light and Dark isolates showed similar cytokine profiles to the control strain, while CIM02 and CIM04 behaved differently (p < 0.001), suggesting that differences in the surface of the isolates can influence host-fungus interaction. MICs for amphotericin B, terbinafine, caspofungin, micafungin, itraconazole, fluconazole, and voriconazole were obtained (CLSI M38-A2/M27-A3). Pairwise comparisons showed distinct MICs between Sporothrix Light and Dark isolates, higher than at least two-fold dilutions, to at least one of the antifungals tested. Isolates from the same pair displayed discrepancies in relation to fungistatic or fungicidal drug activity, notably after itraconazole exposure. Since S. brasiliensis Light and Dark isolates show disparate phenotypic parameters it is quite possible that coinfection represents a common occurrence in the hyperendemic area, with potential clinical implications on feline sporotrichosis dynamics. Alternatively, future studies will address if this specie may have, as reported for other fungi, broad phenotypic plasticity.


Assuntos
Coinfecção/microbiologia , Sporothrix/genética , Esporotricose/microbiologia , Animais , Brasil/epidemiologia , Gatos , Coinfecção/genética , Coinfecção/veterinária , Doenças Endêmicas/prevenção & controle , Doenças Endêmicas/veterinária , Leucócitos Mononucleares/microbiologia , Testes de Sensibilidade Microbiana , Filogenia , Sporothrix/classificação , Sporothrix/isolamento & purificação , Sporothrix/patogenicidade , Esporotricose/epidemiologia , Esporotricose/genética , Esporotricose/veterinária
4.
Med Mycol ; 56(suppl_1): 126-143, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29538731

RESUMO

The description of cryptic species with different pathogenic potentials has changed the perspectives on sporotrichosis. Sporothrix schenckii causes a benign chronic subcutaneous mycosis, Sporothrix brasiliensis is highly virulent, and Sporothrix globosa mainly causes fixed cutaneous lesions. Furthermore, S. brasiliensis is the prevalent species related to cat-transmitted sporotrichosis. Sources of infection, transmission, and distribution patterns also differ between species, and variability differs between species because of different degrees of clonality. The present review article will cover several aspects of the biology of clinically relevant agents of sporotrichosis, including epidemiological aspects of emerging species. Genomic information of Sporothrix spp. is also discussed. The cell wall is an essential structure for cell viability, interaction with the environment, and the host immune cells and contains several macromolecules involved in virulence. Due to its importance, aspects of glycosylation and cell wall polysaccharides are reviewed. Recent genome data and bioinformatics analyses helped to identify specific enzymes of the biosynthetic glycosylation routes, with no homologs in mammalian cells, which can be putative targets for development of antifungal drugs. A diversity of molecular techniques is available for the recognition of the clinically relevant species of Sporothrix. Furthermore, antigens identified as diagnostic markers and putative vaccine candidates are described. Cell-mediated immunity plays a key role in controlling infection, but Sporothrix species differ in their interaction with the host. The adaptive branch of the immune response is essential for appropriate control of infection.


Assuntos
Sporothrix/fisiologia , Esporotricose/diagnóstico , Esporotricose/imunologia , Animais , Antígenos de Fungos/imunologia , Parede Celular/química , Parede Celular/metabolismo , Genoma Fúngico , Especificidade de Hospedeiro/imunologia , Humanos , Técnicas de Diagnóstico Molecular , Sporothrix/classificação , Sporothrix/imunologia , Esporotricose/microbiologia , Esporotricose/transmissão , Virulência
5.
Med Mycol ; 56(3): 288-296, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575449

RESUMO

In severe cases of sporotrichosis, it is recommended to use amphotericin B deoxycholate (D-AMB) or its lipid formulations and/or in association with itraconazole (ITC). Our aim was to evaluate the antifungal efficacy of a poly-aggregated amphotericin B (P-AMB), a nonlipid formulation, compared with D-AMB on systemic sporotrichosis caused by Sporothrix brasiliensis. In vitro assays showed that Sporothrix schenckii sensu stricto and S. brasiliensis yeast clinical isolates were susceptible to low concentrations of P-AMB and D-AMB. Although P-AMB presented a higher minimal inhibitory concentration (MIC) compared to D-AMB, its cytotoxic effect on renal cells and erythrocytes was lower. For the in vivo assays, male BALB/c mice were intravenously infected with S. brasiliensis yeasts, and P-AMB or D-AMB was administered 3 days post-infection. The efficacy of five therapeutic regimens was tested: intravenous monotherapy with P-AMB or D-AMB, intravenous pulsed-therapy with P-AMB or D-AMB, and intravenous therapy with P-AMB, followed by oral ITC. These treatments increased murine survival and controlled the fungal burden in the liver, spleen, lungs, and kidneys. However, only D-AMB monotherapy or the pulsed-therapies with D-AMB or P-AMB led to 100% survival of the mice 45 days post-infection; only pulsed administration of D-AMB was able to control the fungal load in all organs 45 days post-infection. Accordingly, the histopathological findings showed reductions in the fungal burden and inflammatory reactions in these treatment regimens. Together, our results suggest that the P-AMB formulation could be considered as an alternative drug to D-AMB for treating disseminated sporotrichosis.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Esporotricose/tratamento farmacológico , Anfotericina B/administração & dosagem , Anfotericina B/química , Anfotericina B/farmacologia , Animais , Antifúngicos/administração & dosagem , Antifúngicos/química , Antifúngicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Contagem de Colônia Microbiana , Ácido Desoxicólico/administração & dosagem , Ácido Desoxicólico/química , Ácido Desoxicólico/farmacologia , Ácido Desoxicólico/uso terapêutico , Modelos Animais de Doenças , Combinação de Medicamentos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Sporothrix/efeitos dos fármacos , Sporothrix/crescimento & desenvolvimento , Esporotricose/mortalidade , Taxa de Sobrevida
6.
BMC Vet Res ; 14(1): 19, 2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29347940

RESUMO

BACKGROUND: Sporotrichosis is a neglected zoonosis caused by pathogenic fungi belonging to the Sporothrix schenckii complex. In Rio de Janeiro state, this disease reached an epidemic status with over 4700 domestic felines and around 4000 humans affected since the mid-90s. The present study evaluated clinical and epidemiological aspects and also the frequency of colonization and infection by these fungi in healthy cats and among those with suspicious cutaneous lesions, inhabiting four Rio de Janeiro state distinct areas. RESULTS: Three hundred and seventy-one cats were included in two groups: 175 healthy cats [CRG] and 196 cats showing lesions suggesting sporotrichosis [SSG]. Mycological diagnosis allowed SSG animals to be divided in positive [104 cats; +SG] and negative [92 cats; -SG] groups. Nails, oral mucosa and lesions swabs were submitted to culture and potential colonies were subculture for micromorphologycal analysis, dimorphism and molecular tests. In the CRG, only one cat was colonized in the oral cavity [0.57%]; in the -SG group, four animals showed colonization of the nail and/or oral cavity [4.3%]; while the highest frequency of colonization [39.4%] was observed in the +SG. All molecularly typed isolates were identified as S. brasiliensis. CONCLUSION: The results obtained here indicate that healthy cats have a minor role in sporotrichosis transmission within the state of Rio de Janeiro. Conversely, a higher participation of diseased feline in sporotrichosis transmission was evidenced, especially by the colonization of their oral cavity. Sporothrix brasiliensis equally affects and colonizes animals from distinct Rio de Janeiro state areas. Thus, we hypothesize that sporotrichosis is a uniform endemic throughout the state, whose transmission depends mainly on the contact with cats with sporotrichosis. Since Rio de Janeiro displays a world unique epidemic model of the disease, not fully understood, data on the infected and non-infected animals can be of major importance for future strategies of sporotrichosis prevention and control. Finally, considering the importance of the current concept of "one health", the experience here observed can be helpful for distinct epizootias and/or zoonosis.


Assuntos
Doenças do Gato/epidemiologia , Sporothrix/classificação , Esporotricose/veterinária , Animais , Brasil/epidemiologia , Doenças do Gato/microbiologia , Gatos , Dermatomicoses/microbiologia , Feminino , Casco e Garras/microbiologia , Masculino , Boca/microbiologia , Animais de Estimação/microbiologia , Esporotricose/epidemiologia , Esporotricose/transmissão , Zoonoses/epidemiologia , Zoonoses/microbiologia
7.
Eukaryot Cell ; 14(2): 158-69, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25480940

RESUMO

Sporotrichosis is one of the most frequent subcutaneous fungal infections in humans and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual as no sexual stage has ever been reported in Sporothrix schenckii, Sporothrix brasiliensis, or Sporothrix globosa. We have identified the mating type (MAT) loci in the S. schenckii (strain 1099-18/ATCC MYA-4821) and S. brasiliensis (strain 5110/ATCC MYA-4823) genomes by using comparative genomic approaches to determine the mating type ratio in these pathogen populations. Our analysis revealed the presence of a MAT1-1 locus in S. schenckii while a MAT1-2 locus was found in S. brasiliensis representing genomic synteny to other Sordariomycetes. Furthermore, the components of the mitogen-activated protein kinase (MAPK)-pheromone pathway, pheromone processing enzymes, and meiotic regulators have also been identified in the two pathogens, suggesting the potential for sexual reproduction. The ratio of MAT1-1 to MAT1-2 was not significantly different from 1:1 for all three Sporothrix species, but the population of S. brasiliensis in the outbreaks originated from a single mating type. We also explored the population genetic structure of these pathogens using sequence data of two loci to improve our knowledge of the pattern of geographic distribution, genetic variation, and virulence phenotypes. Population genetics data showed significant population differentiation and clonality with a low level of haplotype diversity in S. brasiliensis isolates from different regions of sporotrichosis outbreaks in Brazil. In contrast, S. schenckii isolates demonstrated a high degree of genetic variability without significant geographic differentiation, indicating the presence of recombination. This study demonstrated that two species causing the same disease have contrasting reproductive strategies and genetic variability patterns.


Assuntos
Genes Fúngicos Tipo Acasalamento/genética , Reprodução Assexuada , Sporothrix/genética , Esporotricose/transmissão , Animais , Brasil , Gatos , Surtos de Doenças , Humanos , Sistema de Sinalização das MAP Quinases , Polimorfismo Genético , Sporothrix/patogenicidade , Sporothrix/fisiologia , Esporotricose/veterinária , Virulência/genética
8.
FEMS Yeast Res ; 15(6)2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26260509

RESUMO

Sporotrichosis has been attributed for more than a century to one single etiological agent, Sporothrix schencki. Only eight years ago, it was described that, in fact, the disease is caused by several pathogenic cryptic species. The present review will focus on recent advances to understand the biology and virulence of epidemiologically relevant pathogenic species of the S. schenckii complex. The main subjects covered are the new clinical and epidemiological aspects including diagnostic and therapeutic challenges, the development of molecular tools, the genome database and the perspectives for study of virulence of emerging Sporothrix species.


Assuntos
Genoma Fúngico , Sporothrix/genética , Sporothrix/fisiologia , Esporotricose/microbiologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Antifúngicos/uso terapêutico , Humanos , Técnicas de Diagnóstico Molecular , Esporotricose/diagnóstico , Esporotricose/tratamento farmacológico , Esporotricose/epidemiologia , Virulência
9.
Med Mycol ; 53(1): 34-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25306202

RESUMO

Sporothrix brasiliensis is a highly virulent member of the S. schenckii complex, which is responsible for the emergence of the epidemic sporotrichosis in southeastern Brazil over the last two decades. There are no in vivo studies on the sensitivity of S. brasiliensis to the therapeutic regimens used to treat sporotrichosis. Here, we evaluated the efficacy and safety of antifungal treatments against S. brasiliensis using a murine model of disseminated sporotrichosis. In vitro, S. brasiliensis yeasts were sensitive to low concentrations of amphotericin B-deoxycholate (AMB-d) and itraconazole (ITZ), the latter having greater selectivity toward the fungus. The following treatment regimens were tested in vivo: intravenous AMB-d for 7 days post-infection (p.i.), oral ITZ for up to 30 days p.i., and AMB-d followed by ITZ (AMB-d/ITZ). AMB-d and AMB-d/ITZ led to 100% survival of infected mice at the end of the 45-day experimental period. Although all treatments extended mice survival, only AMB-d and AMB-d/ITZ significantly reduced fungal load in all organs, but AMB-d/ITZ led to a more consistent decrease in overall fungal burden. No treatment increased the levels of serum toxicity biomarkers. Taken together, our results indicate that AMB-d/ITZ is the best therapeutic option for controlling disseminated sporotrichosis caused by S. brasiliensis.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Itraconazol/uso terapêutico , Sporothrix/efeitos dos fármacos , Esporotricose/tratamento farmacológico , Animais , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Tratamento Farmacológico/métodos , Masculino , Camundongos Endogâmicos BALB C , Análise de Sobrevida , Resultado do Tratamento
10.
Med Mycol ; 53(1): 28-33, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25477075

RESUMO

The gold standard for the diagnosis of sporotrichosis consists of the isolation and identification of the fungus from clinical exudates and/or biopsy specimens. However, new technologies offer several advantages over the traditional methods because they are noninvasive and more sensitive in the differential diagnosis of infectious diseases. In the present study, we performed a validation, impact evaluation, and analysis of the applicability of an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of sporotrichosis in different groups of patients in comparison with the reference protocols for the evaluation of diagnostic tests for infectious diseases. We used 177 serum samples that were collected between 1998 and 2008 from patients in a geographic area related to the Rio de Janeiro outbreak of sporotrichosis. The ELISA had a low rate of cross-reactivity based on the reference values for diagnostic tests, and the analysis of the receiver operating characteristic curve revealed an area under the curve of 0.9154. Furthermore, higher accuracy was observed in the serodiagnosis of infections in special groups of patients such as pediatric and human immunodeficiency virus-positive patients. We concluded that this ELISA had a good clinical serological correlation and, therefore, can be considered a new diagnostic tool applicable to all clinical presentations of sporotrichosis.


Assuntos
Surtos de Doenças , Esporotricose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Adulto Jovem
11.
Med Mycol ; 53(1): 60-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25526779

RESUMO

Protein glycosylation pathways are conserved metabolic processes in eukaryotic organisms and are required for cell fitness. In fungal pathogens, the N-linked glycosylation pathway is indispensable for proper cell wall composition and virulence. In Sporothrix schenckii sensu stricto, the causative agent of sporotrichosis, little is known about this glycosylation pathway. Here, using a genome-wide screening for putative members of the glycosyl hydrolase (CAZy - GH) families 47 and 63, which group enzymes involved in the processing step during N-linked glycan maturation, we found seven homologue genes belonging to family 47 and one to family 63. The eight genes were individually expressed in C. albicans null mutants lacking either MNS1 (for members of family 47) or CWH41 (for the member of family 63). Our results indicate that SsCWH41 is the functional ortholog of CaCWH41, whereas SsMNS1 is the functional ortholog of CaMNS1. The remaining genes of family 47 encode Golgi mannosidases and endoplasmic reticulum degradation-enhancing alpha-mannosidase-like proteins (EDEMs). Since these GH families gather proteins used as target for drugs to control cell growth, identification of these genes could help in the design of antifungals that could be used to treat sporotrichosis and other fungal diseases. In addition, to our knowledge, we are the first to report that Golgi mannosidases and EDEMs are expressed and characterized in yeast cells.


Assuntos
Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/metabolismo , Sporothrix/enzimologia , Candida albicans/enzimologia , Candida albicans/genética , Candida albicans/metabolismo , Clonagem Molecular , Biologia Computacional , Expressão Gênica , Glicosídeo Hidrolases/genética , Glicosilação , Sporothrix/genética
12.
Med Mycol ; 53(2): 178-88, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25394542

RESUMO

The in vitro activity of the antifungal agents amphotericin B (AMB), itraconazole (ITC), posaconazole (PSC), voriconazole (VRC), and terbinafine (TRB) against 32 Brazilian isolates of Sporothrix brasiliensis, including 16 isolates from a recent (2011-2012) epidemic in Rio de Janeiro state, was examined. We describe and genotype new isolates and clustered them with 16 older (from 2004 or earlier) S. brasiliensis isolates by phylogenetic analysis. We tested both the yeast and the mycelium form of all isolates using broth microdilution methods based on the reference protocols M38-A2 and M27-A3 (recommended by the Clinical and Laboratory Standards Institute). Considering minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs), TRB was found to be the most active drug in vitro for both fungal forms, followed by PSC. Several isolates showed high MICs for AMB and/or ITC, which are currently used as first-line therapy for sporotrichosis. VRC displayed very low activity against S. brasiliensis isolates. The primary morphological modification observed on treated yeasts by transmission electron microscopy analysis was changes in cell wall. Our results indicate that TRB is the antifungal with the best in vitro activity against S. brasiliensis and support the use of TRB as a promising option for the treatment of cutaneous and/or lymphocutaneous sporotrichosis.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Naftalenos/farmacologia , Sporothrix/efeitos dos fármacos , Esporotricose/microbiologia , Brasil/epidemiologia , Calmodulina/genética , Parede Celular/ultraestrutura , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , Surtos de Doenças , Proteínas Fúngicas/genética , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Sporothrix/classificação , Sporothrix/genética , Sporothrix/ultraestrutura , Esporotricose/epidemiologia , Terbinafina
13.
Med Mycol ; 53(1): 51-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25550387

RESUMO

In order to understand how fungal pathogens can survive inside the host, we must analyze how they evade the fungicidal mechanisms mounted by the host's immune system, such as generation of toxic reactive oxygen species. Studies have shown that infections caused by Sporothrix brasiliensis can be more aggressive than those due to Sporothrix schenckii. Therefore, we propose to analyze and compare the ability of these two pathogenic species to counteract oxidative stress, which, as noted, can be relevant in the host response to infection. We have shown that S. brasiliensis is more resistant to different oxidants, such as H2O2 and menadione, when compared with S. schenckii. Furthermore, our results suggest that the molecular mechanisms by which Sporothrix spp. AP-1 like transcription factors are regulated probably differs from the one seen in other fungal pathogens. Interestingly, comparison between sequences of SbHog1 and SsHog1 stress activated protein kinases suggest that S. brasiliensis Hog1 display mutations that could account for the differences seen in stress sensitivities of these two species. In summary, this is the first study to our knowledge to investigate oxidative stress responses of Sporothrix spp. and provided a model that can be employed in vivo to address how these fungal pathogens can surmount the oxidative stress generated by the host.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/genética , Peróxidos/toxicidade , Transdução de Sinais , Sporothrix/efeitos dos fármacos , Sporothrix/fisiologia , Estresse Fisiológico , Fator de Transcrição AP-1/genética , Biologia Computacional , Regulação Fúngica da Expressão Gênica , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação de Sentido Incorreto , Estresse Oxidativo , Sporothrix/genética , Fator de Transcrição AP-1/metabolismo
14.
BMC Genomics ; 15: 943, 2014 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-25351875

RESUMO

BACKGROUND: The fungal genus Sporothrix includes at least four human pathogenic species. One of these species, S. brasiliensis, is the causal agent of a major ongoing zoonotic outbreak of sporotrichosis in Brazil. Elsewhere, sapronoses are caused by S. schenckii and S. globosa. The major aims on this comparative genomic study are: 1) to explore the presence of virulence factors in S. schenckii and S. brasiliensis; 2) to compare S. brasiliensis, which is cat-transmitted and infects both humans and cats with S. schenckii, mainly a human pathogen; 3) to compare these two species to other human pathogens (Onygenales) with similar thermo-dimorphic behavior and to other plant-associated Sordariomycetes. RESULTS: The genomes of S. schenckii and S. brasiliensis were pyrosequenced to 17x and 20x coverage comprising a total of 32.3 Mb and 33.2 Mb, respectively. Pair-wise genome alignments revealed that the two species are highly syntenic showing 97.5% average sequence identity. Phylogenomic analysis reveals that both species diverged about 3.8-4.9 MYA suggesting a recent event of speciation. Transposable elements comprise respectively 0.34% and 0.62% of the S. schenckii and S. brasiliensis genomes and expansions of Gypsy-like elements was observed reflecting the accumulation of repetitive elements in the S. brasiliensis genome. Mitochondrial genomic comparisons showed the presence of group-I intron encoding homing endonucleases (HE's) exclusively in S. brasiliensis. Analysis of protein family expansions and contractions in the Sporothrix lineage revealed expansion of LysM domain-containing proteins, small GTPases, PKS type1 and leucin-rich proteins. In contrast, a lack of polysaccharide lyase genes that are associated with decay of plants was observed when compared to other Sordariomycetes and dimorphic fungal pathogens, suggesting evolutionary adaptations from a plant pathogenic or saprobic to an animal pathogenic life style. CONCLUSIONS: Comparative genomic data suggest a unique ecological shift in the Sporothrix lineage from plant-association to mammalian parasitism, which contributes to the understanding of how environmental interactions may shape fungal virulence. . Moreover, the striking differences found in comparison with other dimorphic fungi revealed that dimorphism in these close relatives of plant-associated Sordariomycetes is a case of convergent evolution, stressing the importance of this morphogenetic change in fungal pathogenesis.


Assuntos
Doenças do Gato/microbiologia , Proteínas Fúngicas/genética , Sporothrix/genética , Esporotricose/transmissão , Fatores de Virulência/genética , Adaptação Biológica , Animais , Doenças do Gato/transmissão , Gatos , Evolução Molecular , Especiação Genética , Genoma Mitocondrial , Humanos , Filogenia , Sporothrix/classificação , Sporothrix/patogenicidade , Esporotricose/microbiologia , Esporotricose/veterinária
15.
Mycopathologia ; 177(1-2): 111-4, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24309908

RESUMO

Invasive aspergillosis is a leading cause of morbidity and mortality in immunocompromised patients, particularly in individuals with haematological malignancy and in haematopoietic stem cell transplant recipients. Nowadays, the galactomannan (GM) assay has been widely used as an indication of invasive aspergillosis, even though the test is known to generate false-positive results. The aim of this study was to compare the performance of GM and real-time PCR (qPCR) to detected Aspergillus in blood samples obtained from high-risk haematological patients. Haematological patients were screened twice weekly with GM testing, which was performed by the Platelia ELISA kit. An additional sample of whole blood (4 ml) was obtained for the purpose of qPCR testing. Sixty-four samples from 12 patients with haematopoietic stem cell transplant or haematological malignancy were studied. The overall accordance between GM and qPCR tests was 96.9 % (62 samples). Only two samples showed contradictory results, with positive GM test and negative real-time PCR results. Based on the high concordance between GM and qPCR in terms of negative results, the main utility of qPCR could be in the confirmation of positive results seen with GM testing.


Assuntos
Aspergilose/diagnóstico , Aspergillus/genética , DNA Fúngico/genética , Adulto , Aspergilose/sangue , Aspergillus/isolamento & purificação , DNA Fúngico/análise , Reações Falso-Positivas , Feminino , Galactose/análogos & derivados , Neoplasias Hematológicas/microbiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Hospedeiro Imunocomprometido , Masculino , Mananas/análise , Programas de Rastreamento , Pessoa de Meia-Idade , Projetos Piloto , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
16.
Int J Mol Sci ; 15(8): 14505-30, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25141105

RESUMO

Invasive aspergillosis is a life-threatening lung or systemic infection caused by the opportunistic mold Aspergillus fumigatus. The disease affects mainly immunocompromised hosts, and patients with hematological malignances or who have been submitted to stem cell transplantation are at high risk. Despite the current use of Platelia™ Aspergillus as a diagnostic test, the early diagnosis of invasive aspergillosis remains a major challenge in improving the prognosis of the disease. In this study, we used an immunoproteomic approach to identify proteins that could be putative candidates for the early diagnosis of invasive aspergillosis. Antigenic proteins expressed in the first steps of A. fumigatus germination occurring in a human host were revealed using 2-D Western immunoblots with the serum of patients who had previously been classified as probable and proven for invasive aspergillosis. Forty antigenic proteins were identified using mass spectrometry (MS/MS). A BLAST analysis revealed that two of these proteins showed low homology with proteins of either the human host or etiological agents of other invasive fungal infections. To our knowledge, this is the first report describing specific antigenic proteins of A. fumigatus germlings that are recognized by sera of patients with confirmed invasive aspergillosis who were from two separate hospital units.


Assuntos
Antígenos de Fungos/metabolismo , Aspergillus fumigatus/metabolismo , Aspergillus fumigatus/patogenicidade , Antígenos de Fungos/imunologia , Aspergilose/imunologia , Aspergillus fumigatus/imunologia , Humanos , Espectrometria de Massas em Tandem
17.
Braz J Microbiol ; 53(2): 739-748, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35301695

RESUMO

Human sporotrichosis is caused by different Sporothrix species; however, Sporothrix brasiliensis is the main species, usually related to cat transmission in urban areas. A retrospective descriptive study was conducted at the Institute of Infectology Emílio Ribas from 2010 to 2018. Demography, clinical, diagnostic, and therapeutic data were obtained from medical records. Polymerase chain reaction of the calmodulin gene was performed to identify Sporothrix species. In addition, to evaluate the spread of the disease across São Paulo metropolitan region, TerraView version 4.2.2 software was used for geocoding cases according to residence addresses. Kernell's maps using QGIS software version 2.16.3 were constructed to determine the concentration of cases. Results: 260 cases of sporotrichosis were diagnosed between 2010 and 2018. We observed a 700% increment in the number of human cases in the 2016-2018 triennium compared with the 2013-2015 triennium. Female adults with a median age of 46 years old were the predominant infected group associated with cats' exposition at home care, although the age range of all patients was 01 to 86 years old. The main epidemiological risk of acquiring sporotrichosis was contact with cats, reported by 96.5% of the patients. Molecular identification showed that most of the tested isolates were Sporothrix brasiliensis. Lymphocutaneous form was observed in 59.2% and fixed cutaneous form in 37.5% of the patients. Regarding treatment, itraconazole was the main drug used (94.2%) with a cure rate of 98.8%. We observed an important spread of human sporotrichosis involving cat transmission caused by Sporothrix brasiliensis in a densely populated area of São Paulo state. These results are important to alert clinicians and dermatologists about the occurrence and progression of a neglected tropical disease in an urban area and the urgent necessity to include sporotrichosis as a differential diagnosis in the clinical investigation routine.


Assuntos
Doenças do Gato , Sporothrix , Esporotricose , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Brasil/epidemiologia , Doenças do Gato/tratamento farmacológico , Doenças do Gato/epidemiologia , Gatos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Pessoa de Meia-Idade , Doenças Negligenciadas , Estudos Retrospectivos , Esporotricose/tratamento farmacológico , Esporotricose/epidemiologia , Esporotricose/microbiologia , Adulto Jovem
18.
Front Immunol ; 12: 725882, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737741

RESUMO

Monoclonal antibodies (mAbs) are promising alternatives to treat infectious diseases, especially given their potential for applications in combination therapies with antimicrobial drugs to enhance the antifungal efficacy. Protection mediated by mAbs used to treat experimental paracoccidioidomycosis (PCM) has been demonstrated previously. Our aim in the present work was to characterize a monoclonal antibody (mAbF1.4) raised against a cell wall glycoconjugate fraction of Paracoccidioides spp. and to analyze its efficacy combined with trimethoprim-sulfamethoxazole (TMP/SMX) as treatment for experimental PCM. We demonstrated that the epitope recognized by mAbF1.4 is consistent with branched glucose residues present on a cell wall ß-glucan polymer. In vitro, mAbF1.4 increased the phagocytic capacity and nitric oxide concentration induced by the macrophage cell line J774.1A, and this resulted in a significant reduction in the viability of the opsonophagocytized yeasts. In vivo, we detected a significant reduction in pulmonary fungal burdens of mice treated with mAbF1.4 in association with TMP/SMX, which correlated with increased pulmonary concentrations (determined by ELISA) of IFN- Î³, TNF-α, IL-10 and IL-17. In parallel, we observed a decrease in IL-4, suggesting that the treatment was associated with a mixed Th1-Th17 type immune response. Histopathology of lung segments from mice receiving the combination therapy showed a significant reduction in granulomas, which were well-defined, and improved maintenance of lung architecture. These findings demonstrate that mAbF1.4 + TMP/SMX therapy is a promising approach to combat PCM as well as decrease disease sequelae and highlights the potential benefits of immune mediators in PCM combined immunotherapy.


Assuntos
Anticorpos Monoclonais/farmacologia , Imunoterapia/métodos , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Animais , Antifúngicos/farmacologia , Antígenos de Fungos/imunologia , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Pulmão/microbiologia , Pulmão/patologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Paracoccidioidomicose/tratamento farmacológico , Paracoccidioidomicose/microbiologia
19.
Front Immunol ; 12: 749074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867977

RESUMO

In this study, the human immune response mechanisms against Sporothrix brasiliensis and Sporothrix schenckii, two causative agents of human and animal sporotrichosis, were investigated. The interaction of S. brasiliensis and S. schenckii with human monocyte-derived macrophages (hMDMs) was shown to be dependent on the thermolabile serum complement protein C3, which facilitated the phagocytosis of Sporothrix yeast cells through opsonization. The peptidorhamnomannan (PRM) component of the cell walls of these two Sporothrix yeasts was found to be one of their surfaces exposed pathogen-associated molecular pattern (PAMP), leading to activation of the complement system and deposition of C3b on the Sporothrix yeast surfaces. PRM also showed direct interaction with CD11b, the specific component of the complement receptor-3 (CR3). Furthermore, the blockade of CR3 specifically impacted the interleukin (IL)-1ß secretion by hMDM in response to both S. brasiliensis and S. schenckii, suggesting that the host complement system plays an essential role in the inflammatory immune response against these Sporothrix species. Nevertheless, the structural differences in the PRMs of the two Sporothrix species, as revealed by NMR, were related to the differences observed in the host complement activation pathways. Together, this work reports a new PAMP of the cell surface of pathogenic fungi playing a role through the activation of complement system and via CR3 receptor mediating an inflammatory response to Sporothrix species.


Assuntos
Antígenos de Fungos/imunologia , Proteínas do Sistema Complemento/imunologia , Glicoproteínas/imunologia , Macrófagos/imunologia , Sporothrix , Parede Celular/imunologia , Ativação do Complemento , Citocinas/imunologia , Humanos , L-Lactato Desidrogenase/imunologia , Antígeno de Macrófago 1/imunologia , Macrófagos/microbiologia , Moléculas com Motivos Associados a Patógenos/imunologia , Fagocitose
20.
Front Immunol ; 12: 764501, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880863

RESUMO

As there are more than 6 million human deaths due to mycoses each year, there is an urgent need to develop fungal vaccines. Moreover, given the similarities among pathogenic fungi, it may be possible to create a multi-fungi vaccine. In this study, we combined immunoproteomic and immunopeptidomic methods, for which we have adapted a technique based on co-immunoprecipitation (Co-IP) that made it possible to map Histoplasma capsulatum epitopes for the first time in a natural context using murine dendritic cells (DCs) and macrophages (Mφ). Although polysaccharide epitopes exist, this research focused on mapping protein epitopes as these are more immunogenic. We used different algorithms to screen proteins and peptides identified by two-dimensional electrophoresis (2-D) and Co-IP. Seventeen proteins were revealed by 2-D gels, and 45 and 24 peptides from distinct proteins were presented by DCs and Mφ, respectively. We then determined which epitopes were restricted to MHC-I and II from humans and mice and showed high promiscuity, but lacked identity with human proteins. The 4 most promising peptides were synthesized, and the peptides with and without incorporation into glucan particles induced CD4+ and CD8+ T cell proliferation and produced a Th1 and Th17 response marked by the secretion of high levels of IFN-γ, IL-17 and IL-2. These epitopes were from heat shock protein 60, enolase, and the ATP-dependent molecular chaperone HSC82, and they each have a high degree of identity with proteins expressed by other medically important pathogenic fungi. Thus, the epitopes described in this study have the potential for use in the development of vaccines that could result in cross-protection among fungal species.


Assuntos
Vacinas Fúngicas/imunologia , Histoplasma/imunologia , Peptidomiméticos , Proteômica , Animais , Mapeamento de Epitopos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
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